Process for manufacturing elastic tires for wheels.



T. L. GARBONE.

PROCESS FOR MANUFACTURING ELASTIC TIRES FOR WHEELS.

APPLICATION FILED JULY 22. 1908.

Patented Aug. 17, 1909.

TITO LIVIO GARBONE,'O F CHARLOTTENBURG, GERMANY.

I PROCESS FOR MANUFACTURING ELASTIC TIRES FOR WHEELS.

Specification of Letters Patent. Application filed July 22, 1908. SerialNo. 444,754. I

Patented Aug. 17', 1909.

To'all whom it may concern:

Be it known that I, Trro LIvro Cannons, engineer, a citlzen of the SwissRepublic,

residing at 69 Fasanenstrasse, Charlottenburg, near Berlin,-Gcrmany,have invented certain new and useful Improvements in or Relating toProcesses for Manufacturing Elastic Tires for Wheels; and I do herebydeclare the following to be. a full, clear, and exact description of theinvention, such as will enable others skilled in the art to which itaplpertains to make and use the same.

T 0 present invention relates to a process for manufacturing elastictires of the type that contains two or more concentric. spreading ringsof steel or any other suitable material inclosed in a casing. v

The object of the present process is to enable the tire to. bevulcanized in the usual manner as. a whole. This is a matter of somedifliculty as on the one hand the rings cover or casing being tions inthe cover durin vulcanization, the ermetically closed during theoperation, whereas onthe other hand the rings must be freely movableinside the finished tire. According to the present invention this isaccomplished by fixing the two spreading rings to each other in anexactly concentric position by means of some removable holdi-n device,inclosing the rings in the casing an then vulcanizmg in the usualmanner. After vulcanization the holdin device is removed.

' he casing is vulcanized in a known manner by introducing chemicalsubstances into the closed cover which are evaporated by the heatemployed in theprd'cess of vulcanization. The gases produced in thismanner inflate the brand press the layers of the fabric of which thecasing is composed together, so that they remain closely united aftervulcanization. It has however been found that the gases often penetrateinto the tissue of the casing and between the layers, thereby reventingthe layers from becom- I ing close y united. I The consequence of thisis that the partsof the casing do not form-a uniform mass aftervulcanization and have little resistance and also that the tire oftendoes not take the desired form.

In carrying out my invention I obviate these inconveniences by placing acovering of rubber over the spreading ring or rings into which thesubstances to be evaporated are introduced before closing it definitely.

thus pressed against each other without the gases being able topenetrate them.

The process to which the present inven tion relates is illustrated bythe drawing annexed:

Figure 1 is a diagram of the two spreading rings in position forcarrying out the present invention. Figs. 2 and 3 are cross sections ofdifferent forms of execution of the tire manufactured according to thepresent process.

In the drawing A and B are the two spreading rings surrounded in thefinished tire by thecasing D, a cushion C being inserted between theouter ring B and the casing.

-In carrying out the process according to my invention I proceed asfollows:

The two spreading rings A and B are connected by a suitable deviceby-which both rings are fixed in an exactly concentric position. Forinstance a number of screw bolts cZ may be placed through both the ringsby adjusting the screws of which the rings can be fixed in theirposition and at the same time centered. It is however necessary that thefixing device can be removed out of the finished tire or at least thatits strength will not stand a higher strain than is put upon it in thecourse of manufacture, so that it will break as soon as the wheel comesinto use and is exposedto higher strains. I may also employ for thispurpose flexible spokes of rope or any other suitable material instead'of rigid bolts to connect the two spreading rings provided these spokesare exactly strong enough to withstand the strains occurring in .theprocess of manuiacture and break as soon as the wheel is used for actualwork, so that they donot impede the free movement of the spreading ringsinside the casing.

To give theatire the form illustrated in Fig. 2 the two spreading ringsA and'B are inclosed in the rubber covering E into which the substancesto be evaporated are intro-' duced. Then the cushion G of rubber oranother suitable material is put in its place. This cushion is subjectedto a preliminary vulcanization which is carried to such an extent thatthe cushion preserves its form during manufacture and is brought to therequisite degree of softness and elasticity in the subsequent finalvulcanization of the whole tire. The cushion is given the compositionnecessary for this purpose. After putting the cushion C'into its placethe casing D of the tire is formed over it by v the usual way.

In the tire shown in Fig. 3 the inner covering of rubber E surroundsalso the cushion G. The action of the covering during vulcanization ishowever the same as in the arrangement shown in Fig. 2. The gasesproduced by the heat in vulcanization lnflate the covering E and pressit against the layers of tissue forming the casing of the tire, therebyforcing them outward and pressing them against each other. The tire maybe for this purpose inclosed in a metal mold or a casing of fabric notimpregnated with rubber. The mold or fabric in this case prevents therubber, fabrics from expanding and these are in consequence pressedtightly together by the pressure of the gases. from within, these beingat the same time prevented from penetrating into the fabrics. By thismeans the different layers are united intimately during the process ofvulcanization.

The rubber cushion C shown in-Fig. 2 may be also made of porous rubberof the sort employed for the manufacture of rubber sponges but withsmaller pores. For this purpose long strips of rubber of the section ofthe'desired cushion are prepared, made porous and subjected to apreliminary curing. These strips are then placed on the rubber coveringsurrounding the two stretching rings to' form the cushion beforedescribed and the tire is then vulcanized as described. The gases formedin the inside of the covering. E can not in this case penetrate eitherinto the fabric of the casing nor into the pores of the cushion, as theyare inclosed in the rubber covering E. When the tire thus prepared istaken out of the vulcanizer, openings are made in'the casing D on theinside of the tire over the bolts d and the bolts are removed. The tireis then ready for use. The heads of the bolts cl project suflicientlyover the surface of the inner spreading ring that they can be easilyfound '60 by feeling along the inner surface of the tire.

Having now particularly described and ascertained the nature of my saidinvention, and in what manner the same is to be performed, I declarethat what I claim is:

1. A process for vulcanizing elastic tires containing two or moreconcentric spreading rings in a closed casing, as a whole, consisting infirst securing the spreading rings in their concentric position by aremovable fix- '70 ing device, then placing the casing over the rings,and vulcanizing the whole in this posiv tion, the fixing device beingafterward removed.

2. A process for vulcanizing elastic tires contaimng two or moreconcentric spreading rings in a casing, consisting in placing an elasticcushion on the outer spreading ring,

this cushion being subjected to a preliminary vulcanization so that itmay retain it vf during final vulcanization, putting on the casing, andfinally vulcanizing the whole, by which the cushion is given therequisite de gree of softness and elasticity.

3. A process for vulcanizing elastic tires containing two or moreconcentric spreading. rings in a closed'casing, as a whole, consistingin securing the spreading rings in their relative position in the casingduring vulcanization by removable bolts, the heads of 90,

which project over the inner surface of the spreading ring so that-thebolts can be easily found and removed after an opening has been made inthe casing.

, In testimony, that I claim the foregoing as my invention, I havesigned my name in presence of two subscribmg witnesses.

rrro IvIo CARBONE.

